Q1: Laboratory determination of the dif-fusivity of vapor is done by __________ method.

ANS:C - Winkel mann's

Laboratory determination of the diffusivity of vapor is typically done by the wetted wall column method. In the wetted wall column method, a vertical glass column is filled with a porous material, such as glass beads, and one side of the column is wetted with the liquid in which the vapor diffuses. The vapor diffuses through the porous material to the dry side of the column, where it is measured using appropriate instrumentation. By monitoring the concentration profile of the vapor along the column over time, the diffusivity of the vapor can be determined experimentally. Gilliland's, Winklemann's, and Wike's methods are not commonly associated with the laboratory determination of vapor diffusivity. They may be associated with other aspects of chemical engineering or laboratory experiments, but they are not specific methods used for determining vapor diffusivity.